1. Field of the Invention
This invention relates to curable epoxy resins, and more particularly to epoxy resins cured with a reaction product of imidazole and an aldehyde.
2. Related Publications
Imidazole and imidazole derivatives are commonly used epoxy curing agents. However, imidazole is a solid material and, therefore, difficult to use conveniently when curing liquid epoxy systems.
Japanese Pat. No. J59190972-A, which is equivalent to EP No. 126531-A, discloses the reaction products of 2-ethyl-4-methyl imidazole and formaldehyde to form bis-imidazole products for use as epoxy curing agents.
In the present invention it has been discovered that a reaction product of solid imidazole or 2-methyl imidazole with an aldehyde in equal or greater molar quantity is, in most cases, a liquid which is easily dispersed uniformly into epoxy resins thereby providing a new and useful epoxy resin curing agent.